Depth limiter for robotically assisted arthroplasty

Abstract

A robotically controlled depth limiter for a reamer, the depth limiter including a cylindrical housing configured to encompass a portion of a driveshaft of a reamer. The cylindrical housing can define a bore extending therethrough. The depth limiter can include a depth stop engaging the cylindrical housing within the bore, and define an opening configured to receive the driveshaft of the reamer. The depth stop can be configured to receive a signal via processing circuitry of a robotic arm to operate the depth stop to limit distal translation of the driveshaft relative to the cylindrical housing to control a cutting depth of the reamer.

What is claimed is: 
     
       1. A method of robotically controlling a reamer, the method comprising:
 using processing circuitry, controlling movement of a robotic arm to position an end effector affixed to a distal end of the robotic arm at an acetabular surface of a patient, the end effector including a reamer extending distally therefrom; 
 receiving a first radiographic image of the reamer and the acetabular surface of the patient to determine a first maximum cutting depth in the acetabular surface; and 
 using the processing circuitry, electrically adjusting, based on the first radiographic image, a depth controller coupled to the reamer, to configure the depth controller to limit a maximum cutting depth of the reamer to the first maximum cutting depth. 
 
     
     
       2. The method of  claim 1 , further comprising activating the reamer to ream the acetabular surface of the patient to the first maximum cutting depth. 
     
     
       3. The method of  claim 2 , further comprising receiving a second radiographic image of the reamer and the acetabular surface of the patient, to determine a second maximum cutting depth in the acetabular surface. 
     
     
       4. The method of  claim 3 , further comprising using the processing circuitry, electrically adjusting, based on the second radiographic image, the depth controller coupled to the reamer, to configure the reamer to limit the maximum cutting depth of the reamer to the second maximum cutting depth. 
     
     
       5. The method of  claim 4 , further comprising activating the reamer to ream the acetabular surface of the patient to the second maximum cutting depth. 
     
     
       6. The method of  claim 1 , wherein controlling the robotic arm to position the end effector affixed to the distal end of the robotic arm at the acetabular surface of the patient includes using a camera affixed to the reamer. 
     
     
       7. The method of  claim 1 , wherein the depth controller includes a housing and an adjustable depth stop disposed within the housing. 
     
     
       8. The method of  claim 7 , further comprising monitoring a position of the adjustable depth stop using a linear encoder. 
     
     
       9. The method of  claim 1 , wherein the reamer includes a driveshaft that is operably coupled to the depth controller. 
     
     
       10. The method of  claim 9 , wherein the depth controller includes an adjustable depth stop, and wherein the first maximum cutting depth corresponds to a position of the adjustable depth stop. 
     
     
       11. A method of robotically controlling a reamer, the method comprising:
 using processing circuitry, controlling movement of a robotic arm to position an end effector affixed to a distal end of the robotic arm at an acetabular surface of a patient, the end effector including a reamer extending distally therefrom, the reamer including a reamer head coupled to a driveshaft; 
 receiving a first radiographic image of the reamer and the acetabular surface of the patient to determine a first maximum cutting depth in the acetabular surface; 
 using the processing circuitry, electrically adjusting, based on the first radiographic image, a depth controller coupled to the reamer, to configure the depth controller to limit a maximum cutting depth of the reamer to the first maximum cutting depth, the depth controller including an adjustable depth stop configured to contact a portion of the driveshaft when the reamer reaches the first maximum cutting depth; and 
 activating the reamer to ream the acetabular surface of the patient to the first maximum cutting depth. 
 
     
     
       12. The method of  claim 11 , further comprising monitoring a position of the adjustable depth stop using a linear encoder. 
     
     
       13. The method of  claim 11 , wherein electrically adjusting the depth controller occurs automatically after the first maximum cutting depth is determined based on the first radiographic image of the reamer and the acetabular surface.